Apparatus for spraying and treating liquids



April 24, 192s. 1,667,291

C. O. LAVETT APPARATUS FOR SPRAYING AND TREATING LIQUIDS Filed Aug. l1.1924 3 Sheets-Sheet 1 Venter ttorngg/J.

Apri1z4, 192s. 1,667,291

C. O. LAVETT APPARATUS FOR SPRAYING AND TREATING LIQUIDS Filed Auq.11.1924 5 sheets-sheet 2 April 24, 192s. l 1,667,291 f c. o. LAVETTAPPARATUS FOR SPRAYING AND TREATING LIQUIDS Filed Aufr.1l. 1924 5Sheets-Sheet 3 sli Eatented Apr.. 24, 1928.

UNITED STATES Y 1,667,291 PATENT .ol-Fica CHARLES O. LAVETT, F BUFFALO,NEW YORK, ASSI'GNOBWBY IESNE ASSIGNMENTS,

- TO BUFFALO FOUNDRY MACHINE CO.,

or NEW Yoan.

OF BUFFALO, NEW YORK. A CORPORATION APPARATUS ron sPnAYING AND TnEArINGLmums.

Application ma August 11, 41924.. semi n. 'man This, invention relatesto an apparatus for spraying liquids preparatory to drying, coolingorcrystallizino the same. Heretofore spraying of liqui s has beenattempted by forcing the same under high pressure through a nozzle; alsoby passing a current of air ,at a high velocity and at right angles tover the outlet end of a small pipe while the inlet end of the same isimmersed in the solution to be sprayed, thereb creating a partial vacuumin the pipe, t el difference 1n pressure forcing the liquid through the'pipe and vaporizing the same at the outlet thereof; and also byrevolving a flat disk horizontally at a high speed and slowly feeding aliquid on top of the disk so that vthe latter would. throw the same offin an atomized form.` I

These methods of spraying are unsatisfactory owing to the become cloggedand necessitate straining the solution, the frequent renewal of thenozzles due to wear, the high air pressure required and theneed'. fora1r com ressors, and the e difficulty of controlling te solution whenfed to a' disk.

Itis the object of the invention to provide a liquid spraying device foruse in drying,

cooling or crystallizingthe same in which the above mentioned objections-are avoided,

and which permits of accomplishing the tiously.

' In the accompanyingdrawin s;

' Figurel, is a-vertical longitu lnal section showing one form of my1mproved spraying apparatus used in connection with an at-y mosphericdrying and crystallizing chamber. Figure 2,V is a top plan view thereof,partly in section. f Figure 3, is a vertical section of a vacuum drumdrying apparatus equipped with another form of my liquid sprayingdevice.

Figure 4 is a longitudinal section of the same.-

Figure 5 is a vertical transverse section of another form of liquidspraying device embodying my invention.

Figure 6,- is a vertical longitudinal secl'tion taken on line 66 .Figure5.

Figure?, 's a, vertical longitudinal section taken on thecorrespondingly numbered line in Figure 5,

likeparts in the severaligures act that the nozzles purpose eiciently,economically@ and expedi-4 Figure 8, is a fragmentary vertical longi-`tudinal section showing a modifiedform of the means for mounting theliquid c'ontrolling blade ofv my'improved spraying device on theadjacent part of the casing.

Figures 9, 10 and 11 are fragmentary longitudinal sections, on anenlarged scale, showing different forms of the s raying ribs arrangedcircumferentially on t e spraying cylinder. f

Similar characters of reference indicate ofthe drawvariously organized,that formof the same shown in Figures 5, 6 and 7, being constructed asfollows z'-V g The numeral 20 representsa feed trou h` o r chamber whichis adapted to contain t e liquid to be sprayed and 21V represents asupply trough or chamber which 1s adapted to contain a supply of suchliquid for replenishing the feed trou The two troughs may be constructed1n any suitable manner but are preferably formed of cast metal as shownin Figures 5, 6 and 7 i Communication is established between thesetroughs in the present example by means of two horizontal conduits 22'arranged below the troughs near opposite enlds s into t e" thereof andopening at their en lower most parts of the `feed and supply troughs bya longitudinal passage 220 and upright passages 23 and 24 so that theliquid can `flow from the supply trough into the feed trough andreplenish the latter as the a hand valve 19. The entrance of the liquidinto the supply trough for maintaining the level of the same in thistrough at a predetermined height is automatically con..- trolled orregulated by a regulating or controlling. valve 26 the. rotary plug ofwhich is connected byan arm 2'( with a float 28 which rises 1 and falls'in response to variation in the level ofthe li uid. l When this leveldrops below normal `the descent ofthe oat opens the valve 26 and admitsliquid and when the normal level has been restored 'the rising floatagain closes the valve, The

ow of the liquid from the supply trough to the feed trough is controlledby regulating v off the inlet passages 24 of the same more arrangedcireumferentially on the or less. Each of these valves is mounted on theinner end of a threaded valve stem 30 which eX-tends lengthwise througha stutling box 31 at the outer end of the respective liquid conduit andis provided externally of this conduit wit-h a handle 32 formanipulating the same. Upon moving the regulating valves 29 inwardly theinlet passages 'are cut olf more and thus retard the flow of liquid fromthe. supply trough to the feed trough and vice versa and thusmaintaining the level of liquid in the feed trough at such a heightduring the operation of the apparatus as will secure the best.'

results. Y

The supply and feed troughs are preferably of semi-cylindrical form incross section and the same are arranged close together-and separatedfrom eachother by a single intervening wall 33 which is about one halfthe height of the-outer walls of these troughs, as shown iIrFigure .5.

Arranged lengthwise and horizontally within the feed troughs is a liquidprojectn roll which in its preferred form has a cy indrieal body 34 anda plurality of ribs e.. riphery ot the body. This roll is rotata'ilymounted within the feed trough so that the same is concentric with 'thebottom of this trough and the ascending part -of the roll is next to thepartit-ion or dividing wall 33h0- tween the troughs. For this purposethis roll is mounted on a horizontal shaft 36 which is journalled insuitable bearings 37 in the end walls of the feed trough andprovidedexternally of the latter with la driven pulley 39'to which power may beapplied by a belt from any suitable source.

The level of the liquid in the feedtrough is maintained at such heightthat t-he lower part of the cylindrical body' and the ribs of theprojecting roll dip into the same a considerable extent so that whenthisr roll rotates vits underside picks up a considerable quantity ofliquid by frictional contact therewith and raises the sa1ne-in the formof a streaml which is projected upwardly on the ascending side of theroll which is next to the wall 33. In order to enable the rollto obtaina firm frictional grip on the liquid and ensure raising a stream ofconsiderable thickness means are provided for holding the liquid againstthe ascending part of. the

roll and confirming the same so that it cannot be throwntangentiallyaway 'from the roll by centrifugal force until' the liquidhas reached the top of the partition'or wall 33. Various means may beemployed for accomplishing this purpose, those shown in. Figures 5 and7, consisting ot a baille having a curved body 40 which is arrangedconcentrically or substantially so relatively to the a'xis of the rolland extends under the latter and upwardly between the ascending sidethereof tothe top of the partition 33 but separated from the roll by anintervening throat. At its opposite ends this baille body is providedwithupright end walls or. flanges 4l vwhich extend along the oppositeends of the roll and con line the liquid in engagement therewith. Thisbaille may be adjusted radially toward and from the roll by any suitablemeans for varying the width of the throat between the roll and thebaille body, this being cll'ected iu the present iustance by a.plurality of adjusting screws Lla secured to the bottom ot' the feedtrough and supporting the baille, as shown in Figure 5, upon runningthese screws inwardly the baffle will be moved closer to the projectingroll and when running the same down the baille will be moved away fromthe roll thus adapting the adhesive effect to the various kinds ofmaterials and conditions to secure the best results.

Means are provided for controlling the quantity of liquid which isprojected from the roll and to obtain a line and uniform spray While thesurplus is returned to the supply trough ready to be again circulated.The means for this purpose shown in Figures 5 and 6 comprif-ies acontrolling blade 43 arranged horizontally `abovethe upper edges of thebaille and the partition 33 and lengthwise of the projecting ro-ll onthe ascending side of the same so that its inner or rfront edge projectsinto the outer part of the stream of liquid which is being lifted by theroll and deflects the same laterally away from the'roll and over theupper end of the partition 33 and into the, supply trough, while theremaining inner part of this stream is projected upwardly and spread outinto fan shaped spray by the centrifugal action of the rotating roll, asshown in Figure 5. This blade may be moved radially toward and from theperiphery of the projecting roll'and also J,adjusted into various'angles relative thereto, this being effected in the structure shown in'Figure 5 by rock arms 44 pivotally connected at their upper end.l byhorizontal longitudinal pins 45 with the end walls of the supply troughand pivot/ally connected at their lower ends by horizontal ylongitudinalscrews 46 with the ends of the blade, adjusting screws or rods 47passing through .Cztulling boxes 48 in the outer longitudinal wall ofthesupply trough, links 49 connecting the inner ends of the adjustingscrews with the'blade, and adjusting nuts 50 journalled in brackets 51on the supply loo lllii lso trough butv oheld against longitudinalmove.-

ing the screw nuts in one direction the blade is moved toward theprojecting roll and vice versa, and upon tilting the blade or arranginthe same radially relatively to the roll t e blade can be adapted to thecharacter 'of the material under treatment.

For the purpose of confining within certain limits the spray of liquidwhich is thrown off by the projecting roll a confining shield 38 isprovided which is arranged over the rear part of the top and thedescending part of the roll and operates to interceptthe rear part ofthe fan shaped stream of liquid spray vand direct the same downwardlybetween this shield andv` the roll so "that the intercepted part of thespray is returned to the feed trough. This shield is preferablycurvedeo'ncentrically with the projectingroll and so mounted that it isadjustable circumferentially relatively .to the roll for the purpose ofcutting off or intercepting the spray at different places as desired orto meet certain requirements. Forl this purpose the shield is secured tolugs 52 on the end walls of the feed trough by means of 'bolts 53passing through circumferential slots54 in the end portions of theshield.

By providing the cylindrical bodv of the projecting roll withcircumferential ribs which form a plurality Aof alternating groovesthere between ay larger area of contact between the roll and liquid isobtained which facilitates theadhesion of the liquid to the roll kandincreases'the liquid lifting and spraying capacity accordin ,f ,fly.lThese .ribs also operate to cut through the liquidwhen the same is of aviscous nature and aid` in obtaining an. effective grip or adhesion ofthe rollion the liquid. y As the-under side of the roll dips `into theliquid the latter fills its circumferentialgrooves.toithe bottom thereofand thereforepicksgkupa. large quantity of liquid. Asthe rollrot-atesfand rises with its ascending part ont of the liquid that partthereof within the lgrooves of ythe roll adjusts itself and graduallymoves under the effects of centrifugal force from the inner to the outerparts of the walls of the grooves formed by the ribs so that the speedof the liquid is gradually increased land finally the liquid is thrownoff the roll in a. finely divided spray from thev time the roll leavesthe liquid vuntil it again dips into the same. Y

, The'employment ofthe controlling blade permits of regulating thedistribution of the liquid and obtaining a steady, continuous anduniform spray notwithstanding` that vthere may be a variation in thelevelof the liquid in the feed trough because the blade can be adjustedto maintain the 'stream of the desired thickness and cut off or inbottomof the drying chamber and.

tercept the excess thickness' of the same vre-lA gardless of anyvariation in the thickness of thisexcess part of the liquid stream. Thisblade also insures'a Icontinuous discharge of the surplus liquid intothe supply trough which is especially advantageous when operating undervacuum for the purpose of destroying foaming ofthe incoming liquid bbreaking up the bubbles and allowing t 1e escape of the air and gaswithin the same.

The angle which should be assumed by the controlling blade relative tothe projecting roll is dependent upon the viscosity of the solutionwhich is to be sprayed and its qualities of adhering to the movingsurface of the projecting roll. When operating on liquids having goodadhesive qualities the controlling blade may be arranged on a radialline from the` axis of the roll, but when the liquid has poor adhesiveproperties then it is necessary to set the blade at such an angle to aradial line of the roll that part from the roll against the blade willbe deflected back again by lthe blade toward the roll and compelled toissue therefrom in the form of a spray after passing the blade.

VThis spraying apparatus can be utilized to advantage for depositingsolid contain- Vor all of the liquid` by centrifugal action ing liquidsupon heated or cooled surfaces for the Cpurpose of drying or cooling thesame an also for cooking the liquids or crystallizing the same,

In Figures 3 and 4 is shown an apparatus for drying liquids bydelivering the same in the form of a spray upony the exterior of aninternally heated drum 55 which latter is rotatably mounted within adrying chamber 56 from which the vapors are forcibly withdrawn throughan outlet 57 so as to create a vacuum within the drying chamber.

. The. interibr of this drum may be heated by steam, hot water,electricity or in any other suitable' manner. The liquid to be dried isdelivered bythe spraying device containingmy invention-through anopening 58 in the against the underside of the drum. For this purposethe upper edges of the feed and supply troughs of the spraying apparatusgaged with the underside of the drying chamber around the bottom opening58 thereof so as to form a tight joint therewith. In vthis constructionthe shield 381 is fixed in a definite position relative tothe'projecting roll instead of being adjustable circumferentia'lly, asshown in Figure 5. yAs the drum 55 turns in the direction of the arrowin Figure 3, the liquid spray delivered against the underside of thesame is levelled bya spreading blade 59 and vbefore the liquid thusdeposited on the drum again reaches the depositing place it has dried onthe drum and is removed therefrom by a scraper knife ing apparatusembodying my improvements operates to deliver a spray of liquid to bedried through an opening 63 into the upper part of a drying chamber 64where the saine encounters a hot current of air which absorbs themoisture in the minute drops of liquid and causesA the dried residuetofall in the form of powder to the bottom of this chamber. The heated airfor this purpose is supplied by a blower from the outlet of which theair first passes through a heater and then enters the drying chamberbelow the spray inlet 63. rlhe heated air passes forward through thedrying chamber as it absorbs the moisture from the sprayed solution andthen escapes through an outlet 66 at the top of the drying 4chamber' andthen passesv through a dust separator'67 which removes any solidparticles which' may have become entrained in the air before the sameescapes to the atmosphere through an outlet flue' 68. rlhe dried orpowdered residue of the solution which drops to the bottom of the dryingchamber is removed therefrom by a conveyer 69,. l

In vthe form of liquid spraying device shown in Figures 1 and 2 theprojecting roll is arranged sufficiently close to the partition 33 thatthe latter serves as a baffle for keeping the liquid close to theascending part of the projecting roll andenabling the same to obtain agood adhesiveI frictional grip thereon. 1n this application of myinvention the rear wall 71 of the feed trough is carried upwardly aroundthe projecting rolla suiiicient extent to serve as a shield for cuttindown the widthof the fan shaped spray o liquid thrown from theprojecting roll and an aux-- iliary controlling blade 72 is alsoemployed between the main blade and the shield 7l. This auxiliary bladefurther reduces the width of the fan shapedspray of liquid as it entersthe drying chamber. l

Instead of pivotally mounting the controlling blade on the adjacent partof the casing, as shown in `Figure 5, substantially the same eifect maybe obtained by'sli'ding the opposite ends of the controlling blade inhorizontal guide ways 7.3 on the casing, one of which is shown in Figure8. j

The ribs of the projecting roll may either be arranged annularly on thecylindrical square lin cross section, as shown at 35 in Figure 2, and at352 in Fig. 10, or the same ma be ta erin" or V-sha )ed in cross sectione l a as shown at 351 and 353 in Figures 9 and l1 respectively. When theribs of the projecting roll are of annular form the front edge of thecontrolling blade may be made of corresponding shape to fit the annulargrooves between the annular ribs of the cylindrical body, as shown at432 and 433 in Figures 10 and l1 respectively, but when the ribs are 'ofspiral Aform the edges of the controlling blade can only approachcloseto the'outer edges of these ribs, and this edge is therefore madestraight, as shown at 43 and 431 in Figures 2 and 9 respectively.

When spiral ribs are employed the same operate to produce a continuousspray of` liquid by each thread or rib, which spray movescontinuously'from one end of the roll to the other.

instead of merely drying or dessicating the liquid sufficient heat maybe supplied to the drumj in the structure shown in Figures 3 and 4, sothat the liquid solution, for eX- ample a mixture of flour and water,may be heated on the drum suiiicient to cook and dry the same in one oeration.

By supplying a coo .ing 4 medium to the interior of the druml the liquidsprayed on the outer side of the same may be either cooled orcrystallized. When drying such liquids as sulphite waste containing 40to 50 percentsolids, and-skim milk containing 30 to 35 percent solids aperipheral speed `of 5() to 60 feet persecond of the projecting ion rollgives satisfactory results, but this speed must be determined inaccordance with the requirements of each liquid depending on itsviscosity, density and other characteristics'. l

It has been^found by mentation with apparatuses of the character`forming the subject of this invention that the surface of the rotarymember, whereby the liquid to be concentrated is lifted, must beprovided with comparatively 'shallow l I '.m'

extensive experiribs so that when the' cylinder engages its undersidewith the surface of .the liquid, the liquid willbe confined within thegrooves formed between the ribs and thereby enable the' sides of thegrooves to obtain a firm grip or hold on the liquid which is muchstronger'than the peripheral surface ofthe bottom of these groovesandthe outered'ges of the ribs. It has also been'found that asubstantial grip or hold. of the cylindrical l' lifting member can onlybe obtained if the liquid is confined close to the underside of, thecylinder and over a substantialv part thereof circumferentiallyQtherwise the li uid, after bein en a ed b the cylinder Wiqllimmediatelyg fiyg ol' agzyiin before it has acquired any considerablemomentum, whereas in the-present case the liquid is conned close to thecylinder for a sufficientl length of time to cause the liquidtopartakcof the speed of the cylinder so that when tioned to dip intothe liquid and project the" liquid to be sprayed, a cylinder rotatablymounted in said trough and provided on itsv periphery withcircumferential ribs, the lower parts of said cylinder and ribs posisamein the form of a spray and means for confining the liquid close to theunderside of said cylinder and ribs.

2. An apparatus for spraying liquid comprising a feed trough adaptedtocontain the liquid to be sprayed, a cylinder mounted in said trough soas to rotate about a 'horizontal axis and' provided on its peripherypwith circumferential ribs, the lower parts of said cylindei1 and ribspositioned to dip into the liquid and project the same in the form of aspray, and means for confining the liquid close. to the rising parts ofsaid cylinder and ribs. i

3. An apparatus for spraying liquid comprising a feed trough adapted tocontain the liquid to be sprayed, a cylinder mounted in sa1d trough soas to rotate about a horizontal axls and provided on its .periphery withcircumferential ribs the lower parts of said cylinder and ribspositioned to dip into the liquid and project the same in the-form ofaspray, and means' for confining the liquid'close to the risin parts ofsaid cylin: der and ribs, comprising a baiiie curved concentrically withthe axis of said cylinder and ribs and arranged close tothe underside ofsaid' cylinder and ribs.

4. An apparatus for spraying liquid comprising a 'feed trough adapted to`contain the liquid to be sprayed, a cylinder mounted in said trough soas to rotate about a horizontal axis and provided on its periphery withcircumferential ribs, the lower parts of said cylinder and ribspositioned to dip into the liquid and project thesame in the form of aspray, and means for confining the liquid close to the rising parts ofsaid cylinder and ribs, comprising a baille curved concentrically withthe axis of said cylinder 'and ribs and arranged close to the undersideof said cylinder and ribs., and means for adjusting said baiile radiallytoward and from said cylinder and ribs.

5. An apparatus for spraying liquid com prising a feed trou h adapted tocontain the liquid to be spraye a projectin roll rotatably mounted in`said trough an positioned to dip with its underside into said liquidand to project the same, and a radial controlling blade arrangedadjacent to the rising sideof said roll and adapted to inter- 76 Y 'cepta part of the stream of liquid lifted'by said roll and direct the sameback into the trough.

6. An apparatus for spraying liquid comprising a feed trough adapted tocontain the liquid to be sprayed, a projecting roll rotatably mounted insaid trough and positioned to dip with its underside into said liquidand to project the same, -a radial controlling blade arranged adjacentto the rising side of said roll and adapted to intercept a part of thestream of liquid lifted by said roll and direct the same back into thetrough and means for adjusting said blade radially toward and from saidroll.

7. An apparatus for spraying liquid comprising a feed trough adapt-edtov contain the j liquid to be sprayed, a cylinder rotatablyl mounted insaid trough and provided on its periphery with circumferential ribs, thelower parts of said cylinder and ribs positioned to dip into the liquidand project the same lin the form of a spray and a radial controllingblade arranged adjacent to the rising side of said cylinder and ribs andadapted to intercept part of the stream of 4 liquid lifted by saidcylinder and ribs and direct the same back into the trough.

8. An apparatus for spraying liquid comprising a feed trough adapted tocontain the liquid to be sprayed, a cylinder rotatably mounted in saidtrough and provided on its periphery with circumferential ribs, thelower parts of said cylinder and ribs positioned to dip into the liquidand project the same in the form of a spray and a controlling bladearranged adjacent to the rising side of said cylinder and ribsandadapted to intercept part of, the stream of liquid by said cylinder andribs, and said blade being provided at its front edgewith teeth'whichproject into the spaces between said ribs.

9. An apparatus for spraying liquids comv .with the lower part of saidtrough, a rojecting roll rotatably mounted in the eed trough andpositioned to dip with its lower part in the liquid therein and projectthe same in the form of a streamand a radial tain the liquid to besprayed, a supply' trough arranged adjacent to the feed trough andadapted to contain a supply of said liquid, a projecting roll rotatablymounted I. adapted to contain a supply of said liquid, av

in the feed trough and positioned to dip with its lower part in theliquid therein and project the same in the form of a stream, a radialcontrolling blade arranged to intercept a part of said stream and directthe same into said supply trough, and means for conducting liquid fromsaid supply trough to said feed trough.

1l. An apparatus for sprayin liquids comprising a feed trough adapted tocontain the liquid to be sprayed, a supply trough arranged adjacent tothe feed trough and projecting roll rotatably mounted in the feed troughand positioned to dip with its lower part in the liquid therein andproject the same in the form of a stream, a radial controlling bladearranged to interceptv a part of said stream and direct the same intosaid supply trough, a conduit for conducting liquid from said supplytrough to said feed trough, and a valve arranged in said conduit forregulating theiiow-of liquidrom the supply trough to said feed trough.

12. An apparaus for spraying liquid .comprising a feed trough adapted tocontain the liqluid to be sprayed, a projectin roll rotatab y mounted insaid feed trougli and positioned to dip with its lower part in saidliquid and to project the same in the form of a stream, a radialcontrolling blade adapted tol intercept a part of said stream on theascending side of said roll, and a shield-arranged'above the roll andadapted to intercept another part of said stream beyond said blade. Y

13. An apparatus for spraying liquid comprising a feed trough adapted tocontain the liquid to be sprayed, a projecting roll rotatably mounted insaid feed trough and posi'- tioned to dip with its lower part in saidliquid and to project the saine in the form of a stream, a radialcontrolling blade arranged adjacent to the ascending side of the rolland adapted to intercept a part of said stream, and a curved shieldarranged concentrically relatively to said roll beyond said blade andadapted to intercept another part of said stream.

14. An apparatus for spraying liquid comprising a feed trough adapted to:contain the liquid to be sprayed, a projecting roll rotatably mountedin said feed 'trough and positioned to dip with its lower part in saidliquid and to project' the same in the form of a stream,a radialcol'ntrolling blade argranged adjacent to the ascending side of the rolland adapted to intercept a part of said stream, a curved shield arrangedconcentrically relatively to said roll beyond said blade and adapted tointercept another part of said stream and means for adjusting saidshield circumferentially about said roll.

CHARLES o. LAVETT.

